Transcriptional regulator. Involved in the initiation of neuronal differentiation. Heterodimers between TCF3 and tissue-specific basic helix-loop-helix (bHLH) proteins play major roles in determining tissue-specific cell fate during embryogenesis, like muscle or early B-cell differentiation. Dimers bind DNA on E-box motifs: 5'-CANNTG-3'. Binds to the kappa-E2 site in the kappa immunoglobulin gene enhancer. Binds to IEB1 and IEB2, which are short DNA sequences in the insulin gene transcription control region.
Specificity
Natural and recombinant Human Transcription factor E2-alpha
Forms a heterodimer with ASH1 and TWIST2. Isoform E12 interacts with RALGAPA1 and FIGLA. Efficient DNA binding requires dimerization with another bHLH protein. Component of a nuclear TAL-1 complex composed at least of CBFA2T3, LDB1, TAL1 and TCF3. Interacts with NEUROD2, PTF1A and TGFB1I1 (By similarity). Homodimer. Heterodimer. Forms a heterodimer with NEUROD1; the heterodimer is inhibited in presence of ID2, but not NR0B2, to E-box element. Interacts with EP300 and UBE2I.